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The New Rheocasting (NRC) process was applied to cast test specimens of the alloy AlSi7Mg plus minor additions of Scandium and Zirconium. In this paper the process for manufacturing of complex shaped components in semi-solid state is introduced. The semi-solid slurry is made from conventional melts by controlled cooling. There is no on - cost on the material. For comparison reasons the classical AlSi7Mg (A356) alloy was cast in a step plate die, heat treated and tested. The same treatment was given to A356 + Sc alloys. Small variations of chemical composition were chosen for the investigation of the formation of intermetallic phases and their behaviour during heat treatment. Microstructural aspects and mechanical properties will be presented. It can be shown that additions of Scandium have a positive influence on hardness and strength of manufactured samples.

In this paper a new processing technique for producing closed cell net shape aluminium foam parts via the melt route developed by Hütte Klein-Reichenbach and ARC Leichtmetallkompetenzzentrum Ranshofen is presented. The new method facilitates the simplest method of producing a metallic foam by bubbling gas through a molten metal matrix composite (MMC). The resulting stable liquid aluminium foam is guided into a mould, where the foam is solidified. The bubble size of the produced foam can be controlled by the new nozzle design of the gas bubbling equipment according to physical principles of bubble formation in molten metals. Homogeneous cellular structures are achieved for mass densities of 0,1 to 0,6 g/cm3 and narrow cell size distribution of 3 to 15 mm +/- 2 mm. An important advantage of aluminium foam produced with this technique is the freedom it offers with the regard to variations of the process parameters and the alloy.

The New Rheocasting Process (NRC) is a novel semisolid casting technology starting from a fully liquid melt with low superheat, which is poured into steel cups and thereby quenched into the semi-solid regime, and then cooled to forming temperature by controlled cooling. Due to the containment of the semi-solid melt in the steel cop it is not necessary to prepare stable alloy slugs for further handling operations and therefore, possible to adjust the fraction solid to the requirements of the casting. Thin walled castings may require lower fraction solid then thicker walled castings. This paper investigates the influence of variations in volume fraction solid on the resulting mechanical properties of the NRC parts. Different fractions solid are equal to different slug temperatures during forming and may result in different surface temperatures in the die. This influence was investigated as well.